Various types of wet gas scrubbers for removing solid and/or liquid particles from gases are known, including those which utilize the so-called Venturi effect. The inlet gas stream to be cleaned here is utilized to decompose the cleaning liquid into extremely fine droplets which capture particle- and droplet-shaped impurities from the gas stream to be cleaned and can thus be discharged.
Simple Venturi gas scrubbers have a central throat region with constant cross-section, to the inlet side of which a cone narrowing in flow direction is adjoined and to the outlet side of which a cone expanding in flow direction is adjoined. Therefore, such gas scrubbers can only be used effectively over small range of gas flow rates. For this reason, more expensive Venturi gas scrubbers have already been proposed, in which the cross-section of the throat region can be varied for different gas flow rates, in order to maintain the cleaning effect.